Exhaust manifold



FIG. 1 is a perspective view of an exhaust manifold according to the present invention;

FIG. 2 is a front view thereof;

FIG. 3 is a left side view thereof;

FIG. 4 is a rear view thereof;

FIG. 5 is a right side view thereof;

FIG. 6 is a top view thereof; and,

FIG. 7 is a bottom view thereof.

The broken lines in the drawings are environmental and form no part of the claimed design. 

CLAIM The ornamental design for an exhaust manifold, as shown and described. 